Have you experienced this? My viewfinder seems to have gotten darker. Does this normally happen? I did notice that my 50 1.8g at 1.8 shows some blades when I look at the glass.
that "thing" is the aperture controller. it's a tab that pushes the corresponding tab on your lens in order to open up the aperture. If it's not functioning correctly, it's not opening up your lens, therefore making your viewfinder darker.
You should look into getting it fixed, since it's a pretty important part of the operation of the camera
Was it like that when you bought it if so take it back and get a replacement or if it has happened since you bought it is down to you.Which ever get it done by the pros as it could in time damage your lens.
